I actually think I have read a fanfic somewhere where that happened. Considering how Pterano is already a father figure of sorts for the young flyer (due to the mysterious absence of Petre's actual father) I don't actual see there being much a difference in the interactions between the two. Now, if Pterano had stayed and helped raise Petrie in this scenery, then that could have lead to interesting changes indeed

. For one, perhaps Petrie would have grown to be a bit more outgoing and less fearful.
What if (perhaps in a depraved version of my already depraved fanfic

) Chomper was turned into a leafeater, while the other members of the gang were turned into sharpteeth?